Japanese Patent Laid-Open No. 2009-63103 discloses an inhibiter switch that detects a selection range of a shift lever for a vehicle.
FIG. 7A and FIG. 7B are diagrams explaining a general configuration of an inhibiter switch according to a conventional example.
An inhibiter switch 100 has a detent plate 101 that rotates about a rotational axis X in association with a change of a selection range of a shift lever for a vehicle, and a movable contact point 102 with a plurality of contact point portions 112 (112a to 112f) arranged in parallel with each other is fixed on an opposing surface of the detent plate 101 to a pole board 105 through a support platform 103.
A fixed contact point 106 comprises a plurality of fixed contact points (106a to 106f), which are each formed in an arc shape as viewed in a direction of the rotational axis X and are disposed by predetermined intervals in a radial direction of the rotational axis X, on an opposing surface of the pole board 105 to the detent plate 101.
A region of each of the fixed contact points 106 (106a to 106f) exposed on an upper surface of the pole board 105 differs depending upon the peripheral direction around the rotational axis X. When the detent plate 101 rotates around the rotational axis X in association with an operation of the shift lever, the fixed contact point 106 (106a to 106f) connected electrically to the movable contact point 102 switches corresponding to an angular position of the detent plate 101 around the rotational axis X, so that a different output signal is output from the inhibiter switch 100.
Here, an assembly of the inhibiter switch 100 will be performed through the following steps (1) and (2).
(1) Step where the detent plate 101 on which the movable contact point 102 is fixed and the pole board 105 equipped with a support member 120 are prepared, and a cylindrical connecting member 104 connected to the detent plate 101 is inserted in a support hole 107 of the pole board 105 to assemble the detent plate 101 and pole board 105 in the direction of the rotational axis X.
(2) Step where the detent plate 101 is rotated around the rotational axis X to insert the detent plate 101 between the support member 120 and the pole board 105, and the contact point portions 112 (112a to 112f) of the movable contact point 102 are inserted between partition walls 109 partitioning the fixed contact points 106 (106a to 106f) adjacent in a radial direction of the pole board 105.
Here, in the conventional inhibiter switch 100, the rotation in the direction of assembling the detent plate 101 to the pole board 105 is restricted in the angular position of abutting on a stopper 110 provided in the pole board 105. On the other hand, the rotation in the direction of removing the detent plate 101 from the pole board 105 is not restricted.
This is because if the restricting means of defining a rotation-possible range in the removal direction is provided, since the rotation in the direction of assembling the detent plate 101 to the pole board 105 is blocked upon assembling the detent plate 101 to the pole board 105, it becomes impossible to assemble the detent plate 101 to the pole board 105.
Here, there are some cases where upon transporting the assembled inhibiter switch 100, vibrations at the transporting cause the detent plate 101 to rotate in the direction of being removed from the pole board 105 and being out of the pole board 105. In this case, the contact point portions 112 (112a to 112f) of the movable contact point 112 mounted on the detent plate 101 and the like are possibly damaged.
Therefore, it is required for the detent plate to be not easily disconnected from the pole board in the inhibiter switch after assembly completion of the detent plate.